After nearly two years of development, the open source Apache Synapse
enterprise service bus (ESB) is ready for prime time with its 1.0 milestone
release.

ESBs (define) enable various applications and components to communicate
with each other in a predictable way for service-oriented architecture (SOA)
(define). With the 1.0 release, Apache Synapse has gone beyond its
initial roadmap and is providing more functions and more performance than
had originally been anticipated.

"We've done huge amounts of pretty cool stuff in here like non-blocking
transport," Paul Fremantle, Apache Web Services PMC Member and Vice
President of Technical Sales at WSO2 Inc., told internetnews.com. "The
result is we took longer but we got more out of it."

Not just more features but more performance, as well. Fremantle explained
that he had expected Synapse to perform well, but when they started doing
the tests it beat expectations. According to Fremantle, the processing
overhead for Synapse is low and it scales up to multiple thousands of
concurrent connections without dropping messages.

When the Apache Synapse project first began in 2005 as an incubated project at the Apache Software
Foundation, the effort was backed by a number of vendors, including Blue
Titan, Infravio, Sonic Software, Iona and WSO2.

Open source SOA startup WS02 is Fremantle's employer and is also providing
commercial support for Synapse. Fremantle was quick to note that the
Synapse project still benefits from the contributions of a number of
vendors.

"We've had consistent contributions from a few key external people. We've
got an IBM committer and we've picked up two or three committers since the
incubator," Fremantle said. While some might argue that WS02 dominates the project, Fremantle doesn't see it that way.

"Fact is we've got a few guys that we've given the freedom to work on this but in term of architecture involvement it's well balanced."

Apache Synapse isn't the only open source attempt at developing an ESB;
Software startup MuleSource is attempting a similar feat.

In 2006 Ross Mason, founder and CTO of MuleSource, told internetnews.com that the Apache Synapse ESB effort, which at the time was in its incubation
stage, didn't meet enterprise expectations.

Fremantle disagrees.

That's not to say that Mule and Synapse need to be competitors. Fremantle
sees the two ESBs as being complementary with Mule providing good support
for legacy integration and Synapse for XML-based approaches.

With the help of WS02, Synapse may well be arguably easier to use than Mule
as well, at least according to Sanjiva Weerawarana, founder, chairman and CEO of WSO2.

"WSO2 has a product called the WSO2 ESB, which is Apache Synapse with a
trivially easy to use AJAX admin console," Weerawarana said. "The WSO2 ESB
is remarkably easier to use compared to Mule, etc., and performs incredibly
well. We will be announcing general availability of that next week."

Though WS02 is a commercial enterprise, Fremantle said that everything
that WS02 does is open source so there isn't a huge distinction of
downloading Synapse from Apache or from WS02. "We're careful to commit core components back to Apache Synapse."

Weerawarana noted that the project has come a long way over the course of
nearly two years, having started with absolutely no code.

"There were challenges along the way but we've used the time to come up with
a killer architecture," Weerawarana said. "Synapse is the first and only ESB
to be truly designed from the ground up for the XML and Web services mediation
problems."

Moving forward, the next release of Synapse is likely to come within three to six months.

"A lot of where it goes from here depends on user feedback," Weerawarana
explained. "We have plans to add more support for distributed execution
amongst other things."